The present invention relates generally to heating, ventilating, and air conditioning (HVAC) systems for a building. The present invention relates more particularly to a predictive cost optimization system for a building HVAC system.
Some building HVAC systems use both a waterside system and an airside system to provide heating or cooling for the building. The waterside system consumes resources from utility providers (e.g., electricity, natural gas, water, etc.) to produce a heated or chilled fluid. The airside system uses the heated or chilled fluid to heat or cool a supply airflow provided to the building.
Previous approaches to airside and waterside optimization explicitly consider the airside and waterside optimization problems separately. For example, U.S. patent application Ser. No. 14/634,609 titled “High Level Central Plant Optimization” uses a cascaded approach to central plant optimization. The cascaded approach performs the airside optimization first to predict the heating and cooling loads of the building. The predicted heating and cooling loads are then provided as a fixed parameter to the waterside optimization, which is performed second to optimize the performance of the central plant. If the airside system is unaware of the energy storage/generation capabilities of the waterside system, the initial airside optimization can be suboptimal. It is difficult and challenging to optimize the performance of both the airside system and the waterside system without introducing significant complexity to the optimization problem.